Automatic door-alarm



J. R. ANDERSON.

AUTOMATIC DOOR ALARM.

APPLiCATION FILED SEPT. H3. HH 7.

1,304,243. Patented May 20, 1919.

2 SHEETS-SHEET I.

I. R. ANDERSON.

AUTOMATIC DOOR ALARM.

APPLICATION man saw. m. 1am.

1,304,243. Patented May 20, 1919.

Z SHEETS-SHEET 2.

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JAMES R. ANDERSON, 0F LONACO'NI NG, MARYLAND.

AUTOMATIC DOOR-ALARM.

Specification of Letters Patent. Patented 20, 1919.

Application filed September 18, 1917. Serial No. 192,005.

To all whom it may concern Be it known that I, JAMES R. ANDERSON, a citizen of the United States, residing at Lonaconing, in the county of Allegany and State of Maryland, have invented certain new and useful Improvements in Automatic Door-Alarms; and I do hereby declarethe following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to an automatic alarm especially adapted for use upon doors or windows and has for one of its objects the provision of a device of this character, which will automatically give an alarm when either the door or window is opened.

Another object of this invention is the provision of a supporting casing adapted to be secured adjacent the door or window and having a spring actuated arm adapted to be released by the door or window to sound an alarm.

A further object of this invention is the provision of an automatic alarm of the above stated character, which shall be simple, durable and eflicient, and which may be manufactured and sold at a comparatively low cost.

With these and other objects in View, the invention consists in certain novel features of construction, combination and arrangement of parts hereinafter more fully described and claimed.

For a complete understanding of my invention, reference is to be had to the following description and accompanying drawing, in which:

Figure 1 is a side elevation of an automatic alarm constructed in accordance with my invention, illustrating it applied to a door,

Fig. 2 is a similar view illustrating the same applied to a window,

Fig. 3 is a vertical sectional view illustrating the various positions occupied by the arm Fig. 4 is an end elevation of the device illustrating the means for preventing the arm from engaging the cap,

Fig. 5 is a detail sectional view illustrating the means for preventing the arm from engaging the cap,

Fig. 6 is a sectional view taken on the line 66 of Fig. 5,

Fig. 7 is a detail sectional view illustrating the means for securing one end of the spring,

Fig. 8 is a detail sectional view taken on the line 8-8 of Fig. 5, illustrating the means of supporting the catch,

Fig. 9 is a perspective view of a modified form of supporting casing.

Referring in detail to the drawing, the numeral 1 indicates a supporting plate, which is secured to a door frame 2 by fasteners 8. An upper spacing block 4 is secured I to the plate 1 and has secured thereto, an outer plate 5. A spacing block 6 is secured to the supporting plate 1 and to the outer plate 5, which cooperates with the aforedes'c ribed parts in forming a supporting casing. A shaft 7 is secured to the front and rear plates 1 and front plate 5 and has wound thereon, a spring 8, one end of which is disposed between a pair of lugs 9 formed upon the front plate 5, as shown in Fig. 7. The lugs 9 may be secured upon the plate 5 or struck up therefrom. The other end of the spring 8 is bent to form an actuating arm 10, which has its free end bent to form a finger grip 11. A stop 12 is secured to the rear plate 1, and is adapted to be engaged by the arm 10 to hold the same in an operative position or in a position overlying the door 13.

Secured to the upper end of the plate 1 is a bell 14:, which may be of any desired construction provided with an actuating arm 15, which is adapted to be engaged by the arm 10 when released from the stop 12 by the door 13 so as to sound an alarm, notifying that the door is being opened.

A plug 16 is secured tothe spacing block A and is adapted to support an explosive cap 18 as clearly shown in Fig. 8. When the arm 10 is released from the stop 12, and passes beyond the actuating arm 15 of the bell 14, it engages the cap and explodes the same.

A pin 19 is journaled in the block A and has a handle 20 on one end thereof and on its opposite end is a stop block 21, which is so constructed as to be turned to liein the path of the arm 10 to prevent the same from engagingthe cap 18 when desired.

When desiring to apply my invention to a window, the plate 1 is secured to the frame of the window, by suitable fasteners as clearly shown in Fig. 2 so that the actuating arm 10 overlies the sash 22. An inclined block 23 is secured to the window sash 22 and is adapted to engage the actuating arm to disengage it from the stop 12 upon raising the sash 22 so that an alarm will be given if the sash is partially raised.

Referring to my modified form of invention as shown in Fig. 9, it consists of a casing 24: constructed from a single sheet of material, which is first bent in substantially 'U shaped formation having its arm portions 25 connected at the upper end by a flange 26. The web portion having struck out therefrom, a lip 27 and is provided with an aperture and bent downwardly to be secured to either the door frame or window frame. The actuating arm and the other parts heretofore described are mounted in the arm portions of the casing 24 in the usual manner.

While I have shown and described the preferred embodiment of my invention, it will be understood that minor changes in construction, combination and arrangement of parts may be made Without departing from Copies of this patent may be obtained for five cents each, by addressing the spirit and scope of the invention as claimed.

What is claimed is:

A door alarm comprising relatively spaced plates, a spacing block connecting said plates,- a shaft connecting said plates, a spring coiled aboutsaid shaft and having one end bent to form an actuating arm, a stop secured to the inner plate and adapted to hold the arm in an inoperative position, spaced lugs formed on the outer plate and receiving between the same the other end of the spring, means supporting a cartridge on the block so as to be struck by the arm when released and a stop pivoted to the block and adapted to be turned into the path of the arm when desiring to render the device inoperative.

In testimony whereof I afiiX my signature in presence of two witnesses.

JAMES R. ANDERSON.

W itnesses:

WM. B. BRADLEY, WM. OSCAR MYERS;

the Commissioner of Patents,

Washington, D. G. 

